discord.js, voice channel, streaming, raw PCM, child process

client.js

const BOT_TOKEN = process.env.DISCORD_BOT_TOKEN;
const CHANNEL_ID = process.env.VOICE_CHANNEL_ID;

const { spawn } = require('child_process');
const Discord = require('discord.js');
const prism = require('prism-media');

const client = new Discord.Client();

client.on('ready', async () => {
  console.log(`Logged in as ${client.user.tag}`);

  const ch = await client.channels.fetch(CHANNEL_ID);
  const con = await ch.join();

  const encoder = new prism.opus.Encoder({
    rate: 48000, channels: 2, frameSize: 960
  })

  const cmd = spawn('node', ['raw_pcm_producer.js']);
  const p = cmd.stdout.pipe(encoder);

  const dispatcher = con.play(p, {type: 'opus'})

  dispatcher.on('start', () => console.log('voice is now playing!'));
  dispatcher.on('finish', () => console.log('voice has finished playing!'));
  dispatcher.on('error', console.error);

});

process.on('SIGINT', ()=> {
  client.destroy();
  process.exit();
});

client.login(BOT_TOKEN);

package.json

{
  "name": "voice",
  "version": "1.0.0",
  "description": "",
  "main": "client.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "dependencies": {
    "@discordjs/opus": "^0.3.3",
    "discord.js": "^12.5.1"
  }
}

raw_pcm_producer.js

const fs = require('fs');
const prism = require('prism-media');

fs
  .createReadStream('./audio.ogg')
  .pipe(new prism.opus.OggDemuxer())
  .pipe(new prism.opus.Decoder({ rate: 48000, channels: 2, frameSize: 960 }))
  .pipe(process.stdout);